Bag making and packaging machine

ABSTRACT

A bag making and packaging machine is provided with a feed mechanism, a roll holding portion, a printing mechanism, a former, a longitudinal seal mechanism, a transverse seal mechanism, a cutting mechanism, a first sensor, and a second sensor. The printing mechanism prints information on a film. The former causes the two longitudinal sides of the film to become overlapped. The longitudinal seal mechanism bonds the two longitudinal sides and makes a film tube. The transverse seal mechanism sandwiches and bonds the film tube and makes a transverse seal portion. The cutting mechanism cuts the film tube at the transverse seal portion. The first sensor detects a mark on the film for identifying a cutting position for cutting the film tube. The second sensor detects a mark for specifying a printing position of the film where predetermined information is to be printed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This U.S. National stage application of PCT/JP2015/078702 claimspriority under 35 U.S.C. §119(a) to Japanese Patent Application No.2015-005931, filed in Japan on Jan. 15, 2015, the entire contents ofwhich are hereby incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a bag making and packaging machine.

BACKGROUND ART

A bag making and packaging machine pulls a film for wrapping from a filmroll, makes a bag with the film, and wraps articles with the bag. Marksare regularly printed at a constant interval on the film beforehand. Thebag making and packaging machine uses a sensor to detect the marks inorder to print predetermined information such as the manufacturing dateat an appropriate position on the film, and cut the bag-shaped film atan appropriate position for discharging individual wrapped articles.

The bag making and packaging machine disclosed in Japanese Patent No.3971833 is provided with one sensor for detecting the marks.

SUMMARY OF THE INVENTION Technical Problem

At a factory for manufacturing wrapped articles, the operation of thebag making and packaging machine is temporarily stopped just beforefinishing up one film roll. Next, a new film roll is set on the bagmaking and packaging machine by a worker, and the terminating edge ofthe previous film and the starting edge of the film on the new roll arejoined with an adhesive tape or the like. The operation of the bagmaking and packaging machine is then restarted.

Usually, the positional relationship of the two films is not matched atthe joining portion of the films, whereby the interval between adjacentmarks on either side of the joining portion is improper. As a result,displacement of the positions for printing and cutting may occur nearthe joining portion of the films. The range where such displacement inthe films could extend by the feed path between the farthest two amongthe cutting mechanism, the printing mechanism, and the sensor fordetecting the marks. The film portion having such a displacement must bediscarded.

An object of the present invention is to reduce the amount of film thatmust be discarded with regard to a bag making and packaging machine.

Solution to Problem

A bag making and packaging machine according to a first aspect of thepresent invention wraps an article with a bag made from a film on whicha plurality of marks are printed at constant predetermined intervals ina longitudinal direction. The intervals are defined by a dimension froma first side to a second side of the bag. The second side is opposite tothe first side. The bag making and packaging machine includes a feedmechanism, a roll holding portion, a printing mechanism, a former, alongitudinal seal mechanism, a transverse seal mechanism, a cuttingmechanism, a first sensor, and a second sensor. The feed mechanism feedsthe film from the upstream side toward the downstream side. The rollholding portion holds a film roll onto which the film is wound. Theprinting mechanism is disposed downstream of the roll holding portionand prints predetermined information on the film. The former is disposeddownstream of the printing mechanism and causes the two longitudinaledges of the film to overlap. The longitudinal seal mechanism isdisposed downstream of the former and makes a film tube by bonding thetwo longitudinal edges that are overlapping. The transverse sealmechanism is disposed downstream of the longitudinal seal mechanism andmakes a transverse seal portion that extends in the transverse directionin the film tube by bonding two opposing portions of the film tube. Thetransverse direction is perpendicular to the longitudinal direction. Thecutting mechanism is disposed downstream of the longitudinal sealmechanism and cuts the film tube at the transverse seal portion. Thefirst sensor detects a first one of the marks for specifying a cuttingposition of the film tube to be cut. The second sensor detects a secondone of the marks for specifying a printing position of the film wherethe predetermined information is to be printed.

According to this configuration, the bag making and packaging machinehas the first sensor corresponding to the cutting mechanism and thesecond sensor corresponding to the printing mechanism. Therefore, theprinting mechanism and the cutting mechanism are both able to operate atan optimal timing and, consequently, the amount of film that must bediscarded can be reduced.

A bag making and packaging machine according to a second aspect of thepresent invention is related to the bag making and packaging machineaccording to the first aspect, wherein the second sensor is disposedupstream of the printing mechanism.

According to this configuration, the printing mechanism is able operateat an appropriate timing because the printing mechanism is able to use adetection signal of the second sensor disposed further upstream than theprinting mechanism itself.

A bag making and packaging machine according to a third aspect of thepresent invention is related to the bag making and packaging machineaccording to the first aspect or the second aspect, wherein the firstsensor is disposed downstream of the longitudinal seal mechanism andupstream of the cutting mechanism.

According to this configuration, the length of the feed path from thefirst sensor to the cutting mechanism is small and, therefore, there isless concern that a measurement error will affect the position on thefilm learned by a control circuit. Therefore, the cutting mechanism isable to operate at a more accurate timing.

A bag making and packaging machine according to a fourth aspect of thepresent invention is related to the bag making and packaging machineaccording to the first aspect or the second aspect, wherein the firstsensor is disposed downstream of the printing mechanism and upstream ofthe former.

According to this configuration, the first sensor used to allow thecutting mechanism to operate at an appropriate timing can be disposed ata location that facilitates installation.

A bag making and packaging machine according to a fifth aspect of thepresent invention is related to the bag making and packaging machineaccording to any one of the first to fourth aspects, wherein the lengthof the feed path from the roll holding portion to the printing mechanismis equal to or more than three times as long as the dimension of thebag.

According to this configuration, the amount of film that must bediscarded can be reduced regardless of whether the distance of the feedpath from the roll holding portion to the printing mechanism isrelatively long.

A bag making and packaging machine according to a sixth aspect of thepresent invention is related to the bag making and packaging machineaccording to any one of the first to fifth aspects, wherein the lengthof the feed path from the printing mechanism to the cutting mechanism isequal to or more than three times as long as the dimension of the bag.

According to this configuration, the amount of film that must bediscarded can be reduced regardless of whether the distance of the feedpath from the printing mechanism to the cutting mechanism is relativelylong.

A bag making and packaging machine according to a seventh aspect of thepresent invention is related to the bag making and packaging machineaccording to any one of the first to sixth aspects, and is furtherprovided with a printing inspection mechanism and a third sensor. Theprinting inspection mechanism inspects whether or not the predeterminedinformation is printed appropriately. The third sensor detects locationof the marks for specifying the timing to enable the printing inspectionmechanism to operate. The third sensor is disposed upstream of theprinting inspection mechanism.

According to this configuration, the bag making and packaging machinehas the printing inspection mechanism and the third sensor thatcorresponds to the printing inspection mechanism. Therefore, theinformation printed on the film by the printing mechanism can beverified more accurately.

A bag making and packaging machine according to an eighth aspect of thepresent invention is related to the bag making and packaging machineaccording to any one of the first to seventh aspects, and is furtherprovided with a feed length changing mechanism. The feed length changingmechanism changes the length from the printing mechanism to the cuttingmechanism of the film fed by the feed mechanism. The feed mechanism isable to stop once for each time the film is fed by the bag dimension.The printing mechanism and the cutting mechanism both operate in thestoppage.

According to this configuration, the processing speed of the bag makingand packaging machine can be improved because the feeding of the film isstopped only when the printing mechanism and the cutting mechanismoperate at the same time. Furthermore, the verification accuracy of thefeeding state is improved because the position of the film isdouble-checked by two sensors that detect location of the marks.

A bag making and packaging machine according to a ninth aspect of thepresent invention is related to the bag making and packaging machineaccording to any one of the first to eighth aspects, wherein the feedmechanism is able to stop twice for each time the film is fed by thedimension of the bag. One of the printing mechanism and the cuttingmechanism operates in the first stoppage. The other of the printingmechanism and the cutting mechanism operates in the second stoppage.

According to this configuration, the processing speed of the bag makingand packaging machine is improved.

Advantageous Effects of Invention

The amount of film that must be discarded can be reduced according tothe bag making and packaging machine according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a configuration of a bag making andpackaging machine 100 according to a first embodiment of the presentinvention.

FIG. 2 is a plan view of a film F.

FIG. 3 is a perspective view of a film tube FT subjected to alongitudinal seal.

FIG. 4 is a perspective view of the film tube FT subjected to atransverse seal.

FIG. 5 is a block diagram of a control circuit 200 mounted in the bagmaking and packaging machine 100.

FIG. 6 is a schematic view of a configuration of a bag making andpackaging machine 100A according to a second embodiment of the presentinvention.

FIG. 7 is a schematic view of a configuration of a bag making andpackaging machine 100B according to a third embodiment of the presentinvention.

DESCRIPTION OF EMBODIMENTS First Embodiment (1) Overall Configuration

FIG. 1 shows a configuration of a bag making and packaging machine 100according to a first embodiment of the present invention. The bag makingand packaging machine 100 is provided with a feed mechanism 10, a rollholding portion 20, a printing mechanism 30, a printing inspectionmechanism 40, a feed length changing mechanism 50, a former 60, alongitudinal seal mechanism 70, a transverse seal mechanism 75, acutting mechanism 80, a first sensor 91, and a second sensor 92.

(2) Detailed Configurations

(2-1) Feed Mechanism 10

The feed mechanism 10 feeds a film F for wrapping fed out from the rollholding portion 20.

FIG. 2 illustrates the film F. The film F extends lengthwise in alongitudinal direction L and has a constant width that extends in atransverse direction W which is perpendicular to the longitudinaldirection L. A pattern for use as a bag for product wrapping isrepeatedly printed on the film F at each dimension D. A plurality ofmarks M are also printed on the film F at regular intervals, where eachinterval is also equal to the dimension D in the longitudinal directionL. When the film F is finally fabricated into a bag, the dimension Dbecomes the distance between the top side and the bottom side of thebag, or the distance between the left side and the right side of the bagaccording to the design of the bag.

Returning to FIG. 1, the film F is fabricated into the shape of a bag inthe course of the feed mechanism 10 feeding the film F. The feedmechanism 10 finally discharges a wrapped product WP that is filled andsealed.

The feed mechanism 10 has a plurality of rollers, which are not providedwith reference numerals, a pull-down belt 15, a discharge conveyor 19,and a feed length changing mechanism 50 to be mentioned below.

(2-2) Roll Holding Portion 20

The roll holding portion 20 is provided upstream in the feed path formedby the feed mechanism 10. The roll holding portion 20 holds a film rollFR. The film roll FR has a core and the film F which is wound onto thecore and extends in the longitudinal direction.

The feed mechanism 10 holds one end of the film F and draws out the filmF from the roll holding portion 20.

(2-3) Printing Mechanism 30

The printing mechanism 30 prints predetermined information such as themanufacturing date or the like at an appropriate position on the film Fduring feeding. As a result, the predetermined information is printed oneach of the wrapped products WP finally discharged from the bag makingand packaging machine 100.

The length of the feed path from the roll holding portion 20 to theprinting mechanism 30 is equal to or more than three times as long asthe dimension D of the bag. Consequently, a space for disposing themechanisms from the roll holding portion 20 to the printing mechanism 30can be easily obtained.

(2-4) Printing Inspection Mechanism 40

The printing inspection mechanism 40 includes a camera.

The printing inspection mechanism 40 inspects whether the predeterminedinformation printed by the printing mechanism 30 is printed on the filmF in a correct manner, or not. Specifically, the printing inspectionmechanism 40 determines whether the sharpness of the printing, thecontents of the information, the position of the printing, or the likeis appropriate or inappropriate.

(2-5) Feed Length Changing Mechanism 50

The feed length changing mechanism 50 is one of the components of thefeed mechanism 10 and changes the position of some parts in order toadjust the length of the feed path of the film F between the printingmechanism 30 and the cutting mechanism 80.

The feed length changing mechanism 50 has a moveable roller 51 and afixed roller 52. The film F is fed from the upstream side to themoveable roller 51, and then fed to the fixed roller 52, and then is fedtoward the subsequent former 60.

The rotating axis of the moveable roller 51 is moved in a movementdirection S by a movement mechanism that is not illustrated. The fixedroller 52 is able to rotate at a fixed position. The length of the feedpath of the film F is changed by the movement of the moveable roller 51.

(2-6) Former 60

The former 60 is used for rounding the film F fed in a flat state andcausing the two longitudinal sides of the film F to become overlapped.The former 60 has a cylindrical member. The internal space of thecylindrical member is used as a filling path for filling articles bewrapped in the bag formed with the film F.

(2-7) Longitudinal Seal Mechanism 70

The longitudinal seal mechanism 70 bonds the two longitudinal sides ofthe film F overlapped by the former 60. The longitudinal seal mechanism70 has a heater. The heat produced by the heater temporarily softens theoverlapping portions of the film F, whereby bonding is performed suchthat the overlapping portions are fused and/or bonded to one another.

FIG. 3 illustrates the film tube FT made by bonding and having a tubularshape. A longitudinal seal portion SL is formed on the film tube FT dueto the bonding.

(2-8) Transverse Seal Mechanism 75

Returning to FIG. 1, the transverse seal mechanism 75 bonds two opposingportions on the film tube FT.

The transverse seal mechanism 75 has a first member 751 and a secondmember 752 that face each other on either side of the feed path. Thefirst member 751 and the second member 752 are able to approach eachother and move away from each other by means of a motor that is notillustrated. The first member 751 and the second member 752 both haveheaters.

The bonding of the film tube FT is carried out in the following manner.First, the first member 751 and the second member 752 approach eachother and press the film tube FT. Two opposing locations that sandwichthe internal space of the film tube FT are the portions to be pressed.The pressing is performed across the entire dimension in the widthdirection of the film tube FT. Next, heat is applied by the heaters ofthe first member 751 and the second member 752 to the pressed portion ofthe film tube FT. As a result, the pressed portion is softened andbonded. Finally, the first member 751 and the second member 752 stoppressing and move away from each other.

FIG. 4 illustrates the film tube FT subjected to a bonding process bythe transverse seal mechanism 75. The film tube FT has a transverse sealportion SW formed by the bonding process of the transverse sealmechanism 75.

Returning to FIG. 1, the film tube FT is filled with articles of theamount for one bag through the internal space of the former 60 each timean operation of the transverse seal mechanism 75 is finished.

(2-9) Cutting Mechanism 80

The cutting mechanism 80 is provided in the transverse seal mechanism75. The cutting mechanism 80 has a blade 801 and a receiving portion802. The blade 801 is provided in the first member 751 and is able toexsert and retract. The receiving portion 802 is provided in the secondmember 752 and is able to receive the exserted blade 801.

A cutting position CP that is cut by the cutting mechanism 80 isindicated in FIG. 4. The cutting position CP is in the transverse sealportion SW.

Returning to FIG. 1, the blade 801 exserts toward the receiving portion802 in the cutting operation of the cutting mechanism 80. As a result,individual wrapped products WP are cut off.

The length of the feed path from the printing mechanism 30 to thecutting mechanism 80 is equal to or more than three times as long as thedimension D of the bag. Consequently, a space for disposing themechanisms from the printing mechanism 30 to the cutting mechanism 80can be easily obtained.

(2-10) First Sensor 91

The first sensor 91 is a sensor for detecting the marks M (FIG. 2)printed on the film F for identifying the cutting position CP (FIG. 4)to be cut on the film tube FT.

The first sensor 91 is disposed upstream of the cutting mechanism 80 inthe feed path, and is specifically disposed between the printinginspection mechanism 40 and the feed length changing mechanism 50.

(2-11) Second Sensor 92

The second sensor 92 is a sensor for detecting the marks M (FIG. 2)printed on the film F for identifying the printing position to print thepredetermined information on the film F.

The second sensor 92 is disposed upstream of the printing mechanism 30in the feed path.

(3) Control Circuit

(3-1) Overall Configuration

FIG. 5 illustrates a control circuit 200 for controlling the bag makingand packaging machine 100. The control circuit 200 (also referred to asa controller) has a CPU 210 and a memory 220. The CPU 210 has a group ofinput ports and a group of output ports.

(3-2) Inputs

A first detection unit 231, a second detection unit 232, an imageprocessing unit 233, and an operation panel control unit 271 areconnected to the input ports of the CPU 210.

The first detection unit 231 converts signals from the first sensor 91to mark detection signals.

The second detection unit 232 converts signals from the second sensor 92to mark detection signals.

The image processing unit 233 fabricates or processes the data output bythe printing inspection mechanism 40.

The operation panel control unit 271 processes information input by auser through an operation panel 270 mounted on the bag making andpackaging machine 100 for enabling various types of settings, andenables the CPU 210 to read the information.

(3-3) Outputs

A roller motor drive circuit 251, a motor drive circuit for rollerrotating shaft motion 252, a printing mechanism drive circuit 253, aheater drive circuit 254, a motor and heater drive circuit 255, and asolenoid drive circuit 256 are connected to the output ports of the CPU210.

The roller motor drive circuit 251 generates an electric current fordriving the motors for rotating various rollers included in the feedmechanism 10.

The motor drive circuit for roller rotating shaft motion 252 generatesan electric current for driving a motor included in the movementmechanism for moving the rotating shaft of the moveable roller 51.

The printing mechanism drive circuit 253 generates signals or anelectric current for controlling the printing mechanism 30.

The heater drive circuit 254 generates an electric current forcontrolling the heater of the longitudinal seal mechanism 70.

The motor and heater drive circuit 255 generates signals or an electriccurrent for controlling the motor and heaters of the transverse sealmechanism 75.

The solenoid drive circuit 256 generates an electric current forcontrolling the solenoid that governs the extension and retraction ofthe blade 801 of the cutting mechanism 80.

(3-4) Centralized Processing

The CPU 210 detects the marks on the film F via the first sensor 91 andthe second sensor 92. Additionally, the CPU 210 controls the motors forrotating the various rollers included in the feed mechanism 10.

Therefore, the CPU 210 is able to learn the positions indicating whereeach mark M is located on the film F at any timing.

(4) Operations

Returning to FIG. 1, the “continuous operation” executed by the bagmaking and packaging machine 100 will be discussed next.

The feed mechanism 10 feeds the film F at a feeding speed that isnormally constant.

Because the control circuit 200 (FIG. 5) knows the time when each one ofthe marks M is detected by the second sensor 92 as well as the distancethat the film F has been fed by since that time, it calculates thetiming for operating the printing mechanism 30 from time and distancevalues. Thereafter, the control circuit 200 controls the printingmechanism 30 according to the calculated timing to cause the printing ofthe predetermined information at the appropriate position on the film F.

The feeding of the film F continues. Because the control circuit 200knows the time when each one of the marks M is detected by the secondsensor 92 as well as the distance that the film F has been fed by sincethat time, it calculates the timing for operating the printinginspection mechanism 40 from the time and distance values. Thereafter,the control circuit 200 controls the printing inspection mechanism 40according to the calculated timing to acquire images of the film F to beinspected and the inspection is performed.

Next, after the film F passes through the feed length changing mechanism50, the film F is rounded by the former 60 and the two longitudinalsides of the film F are made to overlap each other. The longitudinalseal mechanism 70 heats the overlapping portion. Consequently, theoverlapping portion is bonded and the film tube FT having thelongitudinal seal portion SL (FIG. 3) is made.

The film tube FT is filled with articles of the amount for one bag inthe previous cycle. The transverse seal mechanism 75 makes a transverseseal portion SW (FIG. 4) at a location of the film tube FT that ishigher than the location where the articles are pooled. The cuttingmechanism 80 makes a cut at the cutting position CP (FIG. 4) in thetransverse seal portion SW. The timing of the operations of thetransverse seal mechanism 75 and the cutting mechanism 80 is determinedby the control circuit 200 (FIG. 5) from the time when a correspondingone the marks M is detected by the first sensor 91 and the distance thatthe film F has been fed by since that time.

The individual wrapped products WP cut in this way are discharged fromthe bag making and packaging machine 100 by the discharge conveyor 19.

(5) Characteristics

(5-1)

The bag making and packaging machine 100 is provided with two sensorsfor detecting the marks M. That is, there is the first sensor 91corresponding to the cutting mechanism 80 and the second sensor 92corresponding to the printing mechanism 30. Therefore, the printingmechanism 30 and the cutting mechanism 80 are able to operate at optimaltimings, respectively, even when a joining portion that may accompanythe replacement of the film roll FR reaches the feed mechanism 10 andthe interval between adjacent marks M becomes an incorrect value otherthan the dimension D. As a result, the amount of film F that must bediscarded can be reduced.

(5-2)

The second sensor 92 is disposed upstream of the printing mechanism 30.The printing mechanism 30 is able to operate at an appropriate timingbecause the printing mechanism 30 is able to use a detection signal ofthe second sensor 92 disposed further upstream than the printingmechanism 30 itself.

(5-3)

The first sensor 91 to be used for enabling the cutting mechanism 80 tobe operated at an appropriate timing is disposed downstream of theprinting mechanism 30 and upstream of the former 60. The feed pathextends in a straight line in this region. Additionally, the fed film Fis in a sheet-shape and has not been rounded yet in this region.Therefore, the first sensor 91 can be installed easily in this region.

(5-4)

The length of the feed path from the roll holding portion 20 to theprinting mechanism 30 is equal to or more than three times as long asthe dimension D of the bag. According to this configuration, the amountof film that must be discarded can be reduced despite the long distanceof the feed path from the roll holding portion 20 to the printingmechanism 30.

(5-5)

The length of the feed path from the printing mechanism 30 to thecutting mechanism 80 is equal to or more than three times as long as thedimension D of the bag. According to this configuration, the amount offilm F that must be discarded can be reduced regardless of whether thedistance of the feed path from the printing mechanism 30 to the cuttingmechanism 80 is long.

(6) Modified Examples

The following describes a modified example of the first embodiment.

(6-1) First Modified Example 1A

(6-1-1) Operation

The bag making and packaging machine 100 according to a first modifiedexample 1A of the first embodiment has the same mechanical configurationas the bag making and packaging machine 100 according to the firstembodiment described in FIG. 1. However, the bag making and packagingmachine 100 according to the first modified example 1A executes an“intermittent operation” instead of the abovementioned “continuousoperation” in the operation method. That is, stopping and feeding of thefilm F is repeated.

The feed mechanism 10 stops once temporarily for each time the film F isfed by the dimension D (FIG. 2) of the bag. The printing mechanism 30and the cutting mechanism 80 both operate in the stoppage period.

In order to make it possible for both the printing mechanism 30 and thecutting mechanism 80 to operate at the same time, the feed lengthchanging mechanism 50 changes the length of the feed path from theprinting mechanism 30 to the cutting mechanism 80 before the wrappingoperation so as to achieve an optimal value. As a result, the occurrenceof mismatching of the printing and cutting positions can be suppressed.

The timing of the feed stoppage is decided by the control circuit 200from the time when the mark M is detected by the second sensor 92 andthe distance the film F is fed by after that time. Additionally, thecontrol circuit 200 uses the time at which the first sensor 91 detectsthe corresponding one of the marks M, thereby verifying whether or notthe film F has been fed appropriately according to the assumed timing.

When a joining portion of the film enters the feed path, the secondsensor 92 calculates the difference between the distance of adjacentmarks M on either side of the joining portion and the dimension D of thebag. The control circuit 200 adjusts the length of the feed distancefrom the printing mechanism 30 to the cutting mechanism 80 bycontrolling the feed length changing mechanism 50 in response to thevalue of the above difference. As a result, the printing and the cuttingcan be performed appropriately even when a portion that has a mismatchin the distance between the marks M on the film F has arrived.

(6-1-2) Characteristics

According to this configuration, the processing speed of the bag makingand packaging machine 100 can be improved because the feeding of thefilm F is stopped only when the printing mechanism 30 and the cuttingmechanism 80 operate at the same time. Furthermore, the verificationaccuracy of the feeding state is improved because the position of thefilm F is double-checked by two sensors.

(6-2) First Modified Example 1B

(6-2-1) Operation

The bag making and packaging machine 100 according to a first modifiedexample 1B executes a different intermittent operation from theabove-mentioned first modified example 1A.

The feed mechanism 10 is able to carry out the intermittent operationaccompanying two temporary feed stoppages in addition to theintermittent operation accompanying one temporary feed stoppage asexplained in the first modified example 1A. That is, the feed mechanism10 is able to stop twice for each time the film F is fed by the bagdimension D (FIG. 2). The printing mechanism 30 prints the predeterminedinformation on the film F in the first feed stoppage period. The cuttingmechanism 80 cuts the transverse seal portion SW of the film tube FT inthe second feed stoppage period.

The timing of the first feed stoppage is decided by the control circuit200 from the time when the mark M is detected by the second sensor 92and the distance the film F is fed by after that time. The timing of thesecond feed stoppage is decided by the control circuit 200 from the timewhen the mark M is detected by the first sensor 91 and the distance thefilm F is fed by after that time.

Before starting the wrapping operation of the bag making and packagingmachine 100, the length of the feed path of the film F between theprinting mechanism 30 and the cutting mechanism 80 is appropriatelyadjusted by the feed length changing mechanism 50. As a result, the bagmaking and packaging machine 100 is able to perform intermittentoperation with one temporary feed stoppage in the usual case, andperform intermittent operation with two temporary feed stoppages nearthe joining portion of the film F.

(6-2-2) Characteristics

According to this configuration, the need for the operation of the feedlength changing mechanism 50 is made unnecessary so long as the bagmaking and packaging machine 100 produces the same type of wrappedproducts by using the same type of the film F. As a result, theprocessing speed of the bag making and packaging machine 100 can befurther improved.

Second Embodiment (1) Configuration

FIG. 6 illustrates a configuration of a bag making and packaging machine100A according to a second embodiment of the present invention. Thearrangement position of the first sensor 91 in the bag making andpackaging machine 100A differs from that of the bag making and packagingmachine 100 according to the first embodiment. The first sensor 91 isdisposed downstream of the longitudinal seal mechanism 70 and upstreamof the cutting mechanism 80.

(2) Characteristics

The cutting mechanism 80 is able to use the detection signal of thefirst sensor 91 disposed upstream of the cutting mechanism 80 itself andnear the cutting mechanism 80 in order to decide the timing for thecutting operation. Therefore, there is less concern that a measurementerror will affect the position on the film F learned by the controlcircuit 200 because the length of the feed path from the first sensor 91to the cutting mechanism 80 is small. As a result, the cutting mechanism80 is able to operate at a more accurate timing.

(3) Modified Example

The intermittent operation according to the first modified example 1A orthe second modified example 1B of the first embodiment may be applied tothe bag making and packaging machine 100A according to the secondembodiment.

Third Embodiment (1) Configuration

FIG. 7 illustrates a configuration of a bag making and packaging machine100B according to a third embodiment of the present invention. Thearrangement positions of the first sensor 91 and the second sensor 92 inthe bag making and packaging machine 100B are the same as those of thebag making and packaging machine 100 according to the first embodiment.However, the bag making and packaging machine 100B is further providedwith a third sensor 93 and thus differs from the bag making andpackaging machine 100 according to the first embodiment.

The third sensor 93 detects each of the marks M for specifying thetiming to enable the printing inspection mechanism 40 to operate. Thethird sensor 93 is disposed upstream of the printing inspectionmechanism 40 in the feed path, and is specifically disposed between theprinting inspection mechanism 40 and the printing mechanism 30.

(2) Characteristics

The bag making and packaging machine 100B has the printing inspectionmechanism 40 and the third sensor 93 that corresponds to the printinginspection mechanism 40. Therefore, the information printed on the filmF by the printing mechanism 30 can be verified more accurately.

(3) Modified Example

The intermittent operation according to the first modified example 1A orthe second modified example 1B of the first embodiment may be applied tothe bag making and packaging machine 100B according to the thirdembodiment.

1. A bag making and packaging machine for wrapping an article within abag, the machine defining an upstream side and a downstream sidethereof, comprising: a feed mechanism that feeds a film from theupstream side toward the downstream side, the film having a plurality ofmarks on printed one surface thereof at constant intervals in alongitudinal direction of the film, each of the intervals correspondingto a dimension of the bag from a first side of the bag to a second sideopposite to the first side of the bag; a roll holding portion that holdsa film roll onto which the film is wound; a printing mechanism disposeddownstream from the roll holding portion and that prints predeterminedinformation on the film; a former disposed downstream of the printingmechanism and that causes two longitudinal edges of the film to becomeoverlapped; a longitudinal seal mechanism disposed downstream of theformer and that makes a film tube by bonding the two longitudinal edgesthat are overlapping; a transverse seal mechanism disposed downstream ofthe longitudinal seal mechanism and that makes a transverse seal portionthat extends in a transverse direction perpendicular to the longitudinaldirection in the film tube by bonding two opposing portions of the filmtube; a cutting mechanism disposed downstream of the longitudinal sealmechanism and that cuts the film tube at the transverse seal portion; afirst sensor that detects locations of a corresponding one of theplurality of marks for determining a cutting position of the film tubecut by the cutting mechanism; a second sensor that detects the locationsof a corresponding one of the plurality of marks for determining aprinting position of the film where the predetermined information is tobe printed; and a controller connected to former, the longitudinal sealmechanism, the printing mechanism, the cutting mechanism, the firstsensor and the second sensor, the controller being configured todetermine the cutting position of the film tube and operating thecutting mechanism to cut at the cutting position, and determine theprinting position of the film printed by the printing mechanism.
 2. Thebag making and packaging machine according to claim 1, wherein: thesecond sensor is disposed upstream of the printing mechanism.
 3. The bagmaking and packaging machine according to claim 1, wherein: the firstsensor is disposed downstream of the longitudinal seal mechanism andupstream of the cutting mechanism.
 4. The bag making and packagingmachine according to claim 1, wherein: the first sensor is disposeddownstream of the printing mechanism and upstream of the former.
 5. Thebag making and packaging machine according to claim 1, wherein: thelength of a feed path defined from the roll holding portion to theprinting mechanism is equal to or more than three times as long as thedimension of the bag.
 6. The bag making and packaging machine accordingto claim 1, wherein the length of a feed path from the printingmechanism to the cutting mechanism is equal to or more than three timesthe dimension of the bag.
 7. The bag making and packaging machineaccording to claim 1, further comprising: a printing inspectionmechanism that inspects whether or not the predetermined information isprinted appropriately; and a third sensor that detects the mark forspecifying a timing to enable the printing inspection mechanism tooperate, wherein, the third sensor is disposed upstream of the printinginspection mechanism.
 8. The bag making and packaging machine accordingto claim 1, further comprising: a feed length changing mechanism thatchanges a length of the film from the printing mechanism to the cuttingmechanism, the film being fed by the feed mechanism, wherein the feedmechanism is able to stop once for each time the film is fed by thedimension of the bag, and wherein the printing mechanism and the cuttingmechanism both operate in the stoppage.
 9. The bag making and packagingmachine according to claim 1, wherein the feed mechanism is able to stoptwice for each time the film is fed by the dimension of the bag, and oneof the printing mechanism and the cutting mechanism operates in a firststoppage, and the other of the printing mechanism and the cuttingmechanism operates in a second stoppage.
 10. The bag making andpackaging machine according to claim 2, wherein: the first sensor isdisposed downstream of the longitudinal seal mechanism and upstream ofthe cutting mechanism.
 11. The bag making and packaging machineaccording to claim 2, wherein: the first sensor is disposed downstreamof the printing mechanism and upstream of the former.
 12. The bag makingand packaging machine according to claim 2, wherein: the length of afeed path defined from the roll holding portion to the printingmechanism is equal to or more than three times as long as the dimensionof the bag.
 13. The bag making and packaging machine according to claim2, wherein the length of a feed path from the printing mechanism to thecutting mechanism is equal to or more than three times the dimension ofthe bag.